西辽河平原气候及水资源变化特征

Change characteristics of climate and water resources in west Liaohe River Plain

基于1951—2007年通辽、开鲁、扎鲁特3个气象站的降水和气温资料以及通辽市水文勘测局、水务局提供的有关水文资料,对西辽河平原水资源变化进行了研究.结果表明:1951—2007年间,西辽河平原降水量在周期变化中有减少的趋势,降水倾向率为-13.2mm·(10a)-1,降水的不稳定性增加;西拉木伦等4条入境河流的径流量减少,2001—2007年的年均径流量仅为1990—1994年的22.8%;研究期间,西辽河径流量减少,断流日数增加,2001年以来断流至今;与1978年相比,2006年科尔沁区地下水超采区面积增加了8.5倍,漏斗区面积增加了15.5倍;与1980年相比,2006年科尔沁区、开鲁县和奈曼旗地下水位平均埋深分别增加了3.76、2.77和1.93m;20世纪70年代以来,研究区机电井数量持续增长,农业灌溉用水量波动上升,农业用水比例不同程度地下降.开发利用空中水资源、推广节水农业技术和合理布局产业结构是实现西辽河平原水资源可持续利用的有效措施.

Based on the 1951-2007 observation data Of precipitation and temperature from Tongliao, Kailu, and Zhalute meteorological stations as well as the related hydrologic data from Tongliao hydrological survey bureau and water affairs bureau, the change characteristics of the climate and water resources in west Liaohe River Plain were studied. The results showed that in 1951-2007, the precipitation in its periodical changes in study area had a decreasing trend. The tendency rate of precipitation was - 13.2 mm · （ 10 a） ^-1, and the instability of precipitation was increased. The runoff of four inbound rivers including Xilamulun all decreased, with the mean annual runoff in 2001-2007 being only 22.8% of that in 1990-1994. From 1951 to 2007, the runoff of west Liaohe River decreased, and the days of its zero flow increased. Since 2001, the River had been zero flow. The groundwater overdraft area and the funnel area in Keerqin Region in 2006 increased by 8.5 times and 15.5 times, respectively, compared with those in 1978 ; and the average groundwater level in Keerqin Region, Kailu County, and Naiman Banner in 2006 increased by 3.76 m, 2.77 m, and 1.93 m, respectively, compared with that in 1980. Since the 1970s, the number of electromechanical well in study area was increasing, irrigation amount had a fluctuated rise, and the proportion of agricultural water consumption had different extent decrease. Therefore, to exploit and use the water resources in atmosphere, to popularize water-saving irrigation technologies, and to make a reasonable arrangement of industrial structure were the effective measures in realizing the sustainable utilization of water resources in west Liaohe River Plain.